Internal combustion engine cylinder heads and particularly diesel engine cylinder heads are complex castings possessing numerous internal coolant, fuel injector and exhaust gas passages. As pointed out in U.S. Pat. No. 3,973,429, Durgan, et al, in diesel engines higher pressures and temperatures are required for proper combustion of the fuel and under heavy service seals about the fuel injectors and pre-combustion chambers may leak. In addition, cracks may develop in the walls which separate the numerous internal passages which can cause a detrimental intermixing of coolant fluid, exhaust gases, fuel and lubricating oil.
The Durgan patent teaches that cylinder heads and the like can be tested for leaks by removing the engine head from the engine and sealing off the ports which connect the internal coolant passages with the corresponding passages in the engine block, and subjecting the cylinder head passages to compressed air or a fluid under pressure. By applying a soap or other suitable solution to the cylinder head or part to be tested, it is then possible to locate any cracks or leaks between the coolant passages and any other conduit.
A major problem in the pressure testing of cylinder heads is that the heads come in many different sizes and with numerous different configurations of coolant passages and parts thus requiring a variety of plates, plugs, pads and clamps to seal the part to be tested. A number of solutions to facilitate the sealing of a cylinder head for fluid pressure testing are disclosed in U.S. Pat. Nos. 3,360,984, Salsbury et al, 3,973,429, Durgan et al and 4,157,028, Moffett III. As disclosed in the above cited Patents, the parts may be sealed by means of various types of clamping structures. These prior art clamping structures all involve numerous pads, plates, bolts or springs and the clamping mechanisms tend to obstruct the engine head gasket mating surface interfering with access to the head surface for inspection and repair purposes. Also, these prior art clamps are often time consuming to adjust.
The present invention eliminates the shortcomings of the abovementioned prior art by providing an engine cylinder head port closure clamp for sealing the ports of engine cylinder heads or the like, which is of simpler design and is adaptable to virtually all models of cylinder heads. By virture of being able to insert and secure the clamp in either a threaded or non-threaded cylinder head bolt hole of different diameters additional bolts, nuts or tie bars are eliminated permitting the sealing of the engine head ports to be more readily and rapidly accomplished. Also, the clamp of the present invention provides greater access to the cylinder head enabling greater use of inspection and faster more efficient repair of defects.